Wood-chipping apparatus for making chips for chip-boards



March 1, 1966 P. KIRSTEN 3,237,663

WOOD-CHIPPING APPARATUS FOR MAKING CHIPS FOR CHIP-BOARDS Filed NOV. 24, 1964 INYENTOR. Pau/ K/rsfen BY wwwni 6W HIS ATTORNEYS United States Patent ()ffice 3,237,663 Patented Mar. 1, 1966 3,237,663 WOOD-CHIPPIN G APPARATUS FOR MAKING CHIPS FOR CHIP-BOARDS Paul Kirsten, Bonn, Germany, assignor to Industrie-Compagnie Kleinewefers Konstruktionsund Haudelsgesellschaft m.b.H., Krefeld, Germany, a corporation of Germany Filed Nov. 24, 1964, Ser. No. 416,950 3 Claims. (Cl. 144-172) This application is a continuation-in-part of US. Patent application 142,909, filed October 4, 1961 now abandoned.

The present invention relates to a wood-chipping device used to produce chips for chip-boards.

Machines are known for making chips from small pieces of wood waste wherein a cutter spindle, a cutter disc, or the like serves as the tool carrier. The wood which is to be reduced to chips is fed to the cutters of the spindle or disc of the tool carrier vertically or at a given angle. Thus the wood can be fed with the grain parallel or vertical to the rotational axis of the tool carrier.

In these well-known machines, the feeding chute which receives the pieces of wood is so positioned in relation to the tool carrier that a small angle of up to 45 degrees is formed between the peripheral travel of the cutters and the one wall of the chute or its prolongation which forms a fixed blade and serves as a stop for the wood. In this way, when the tool carrier, i.e., the cutter spindle or disc, is rotated, especially the wood remnants in the slot or gap between the fixed blade and the upper surface of the tool carrier are supposed to be drawn in.

This drawing in of the wood into the wedge-shaped slot or gap between the fixed blade and the tool carrier has this disadvantage that depending upon the way in which the chipping tool engages the wood, the latter is drawn more or less strongly toward the wedge-shaped slot and is thus exposed to greatly varying pressures when pressed against the tool carrier. This explains the variation in the thickness of the chips.

The previously known machines for making wood chips from waste wood have this further disadvantage that in continuous open grooves for chips which are frequently used, remnant pieces get into the chip groove and not only block or choke the chip groove, but also permit larger remnant pieces to be formed among the chips, which is by no means desirable.

It is the object of the invention to avoid these disadvantages, the particular aim being to have the wood pressed against the chipping tools with generally uniform pressure. With the device of the invention, it is possible to have the impact pressure exclusively dependent upon the pressure with which the wood is fed and pressed into the feeding chute or channel against the chipping tool. Now there is no longer any danger of pressing the wood remnants into the chipping groove, and thus the disadvantages associated therewith are avoided.

In order to achieve the above-mentioned purpose, we propose to use a wood chipping device for making chips for chip boards having a feeding channel or chute to guide the pieces of wood toward the tool carrier in such a way that their grain is either parallel, perpendicular, or at any given angle to the rotational axis of said tool carrier, and wherein, in accordance with the invention, the peripheral travel of the chipping tool (chip cutter) of the tool carrier forms an angle of approximately 90 degrees with the one wall of the feeding channel or chute or the elongation thereof which serves as a fixed blade.

A further distinguishing characteristic of the invention lies in the fact that the feeding channel or chute is so located in relation to the rotational direction of the tool carrier that the one wall of the feeding channel or chute is in line with or approximately in line with the rotation axis of the tool carrier.

In the wood chipping apparatus of the invention solely the force produced by the wood feeding mechanism and/ or the weight of the wood acts upon the tool carrier. No longer does a component of the cutting force act upon the pieces of wood to press the wood against the cutting tools or tool carrier. Heretofore, the cutting force was split up into lateral forces of which the force acting upon the tool carrier was added to the impact force exerted on the wood by the wood feeding device, e.g., by the feedchains of the feeding chute.

In the drawing, an example of the wood chipping apparatus according to the invention is illustrated:

FIGURE 1 is a schematic vertical section through a vertical feed chute; and

FIGURE 2 is a plan view.

Channel or chute 1 for receiving the wood is substantial ly formed by walls 2 and side plates 2a, 2b. Chains 3 and 4 are guided around return pulleys 5 and 6 and arranged at a distance from each other. They carry spikes or tines 3a, 4a, which travel in slots in the side plates 2a, 2b, and which engage pieces of wood 20 in the chute to assist their travel to a tool carrier 8. The wood which is to be reduced to chips is guided in channel or chute 1 in the direction of arrow 7 to the tool carrier 8 which may be in the form of a horizontally positioned heavy spindle, drum or disc connected to a conventional motor (not shown) for imparting rotation thereto. At the periphery of tool carrier 8, spaced apart chipping tools 9 are located and in front of these in the rotational direction of arrow 10 chipping grooves 11 are situated. Each of the tools 9 is adjustable in a well-known manner to control thickness of the chips. As shown in FIGURE 2, the tools extend across the width of the drum parallel to its central axis 14. However, the tools may also extend diagonally across the drum to form a somewhat helical arrangement. The peripheral travel of the cutting edges of 9b of cutter 9 is represented by the reference numeral 9a.

An extension wall or plate 12 and a fixed wall or blade 13 comprise elougations of side plates 2a and 2b, respectively, between the ends of the chains 4 and the tool carrier 8. The bottom ends of the extension plate 12, the fixed blade 13 and of the walls 2 terminate short of engagement with the chipping tools 9 to provide a clearance for travel therepast and to form a zone in which chips are produced by engagement of the chipping tools 9 with the pieces of wood 20. The carrier 8 brings the tools 9 into the zone wherein the chips are formed and removes the tools from the zone and past the fixed blade 13 which defines an exit side of the zone. As shown, the wall of the chute opposite the fixed blade 13 comprises plates 12 and 2a and has a rigid mounting so that it does not move toward and away from this fixed blade 13.

FIGURE 1 shows that each chipping tool 9 has a mounting upon the carrier 8 such that it is inclined in the direction of travel past the fixed blade 13 and is in a plane which intersects the blade 13 at an acute angle when the tool is opposite the blade 13. Also, this fixed blade 13 is so located relative to the direction of rotation of the carrier 8 and is disposed in the same vertical plane as the axis 14 of rotation of the carrier or so disposed laterally of this vertical plane that when each tool 9 arrives at the fixed blade, it has a motional component which is in an upward direction.

FIGURE 1 shows that chips 21 formed by operation of the wood chipping apparatus collect in the grooves 11 and upon the periphery of the drum and travel from the zone into a hopper 22. As the tool carrier 8 rotates in the direction of the arrow 10, the chips fall out of the 9 a grooves and off the carrier into the hopper after exiting from the zone.

In accordance with the invention, the one wall of the feed channel or chute, in the present case, the wall formed by chain 4, side plate 211, and fixed blade 13 forms an angle a of approximately 90 degrees with the tangent of the path of travel 9a at the end 13a of the fixed blade. Thus, the invention prevents the formation of a Wedgeshaped slot such as has been known from previous woodchipping devices through which wood remnants were able to be drawn in.

As illustrated in the drawing, it is preferred to form angle a between the fixed blade 13 and the tool carrier 8 by so disposing channel or chute 1 in relation to the rotational direction (arrow '10) of the tool carrier 8 that the wall of the feeding channel or chute formed by chain 4, side plate 212 and the fixed wall or blade 13 is in line with or approximately in line with the rotational axis 14 of the tool carrier.

A significant feature of the present apparatus is the motion components of the chipping tools 9 as each tool passes through the chipping zone between plate 12 and blade 13. Each tool should have an upward motion component for substantially the entire time it is Within this zone. If the angle a is 90 degrees and the inner surface of the rear wall or blade 13 is aligned substantially vertically in a plane extending through the axis of rotation of the carrier 8, each tool will have such a component.

Although the angle a need not be exactly a right angle, it should not be greater than about 100 degrees or less than about 80 degrees. Preferably, however, the angle a will be within the preferred range of 85 degrees to 95 degrees.

Where the angle a deviates from 90 degrees within the permissive ranges, the vertical plane defining the inside surface of blade 13 does not extend through axis 14. T o assure a vertical feed, this plane should be substantially perpendicular to a horizontal plane that is disposed substantially parallel to the axis of rotation of the tool carrier.

As shown in FIGURE 1, the wood in that portion of the channel 1 defined by the extension plate 12 and the fixed blade 13 is free from engagement by a motor driven feeder. Accordingly, there is no device in front of the chipping tools 9 or the fixed blade 13 for feeding the wood thereto and no device which moves and urges the wood towards and against the blade 13 except for the chipping tools 9 in their rotational travel.

In the present apparatus channel or chute 1 is vertically positioned so that the wood is positively urged against tools 9 of carrier 8 solely by gravity. Chains 3 and 4 and spikes 3a and 4a are optional preferred apparatus that serve to guide the wood and prevent bridging of elongated pieces within the channel or chute.

While I have shown and described a presently preferred embodiment of my invention, it is to be understood that it may be otherwise embodied within the scope of the following claims.

I claim:

1. Apparatus for making chips from wood for chipboard comprising a horizontally positioned, rotatable drum-like tool carrier with a horizontal axis of rotation, a vertically disposed channel for receiving and conveying pieces of wood to said tool carrier which has a plurality of spaced apart chip forming tools each with a cutting edge and which is adapted to be drivingly connected to motor means for imparting rotation to said carrier and thereby travel to said tool's, said channel being formed by walls including a rear wall, extending towards said carrier and having a terminal end located short of engagement with said tools to form a clearance for travel of said tools therepast, said walls at said terminal end defining a chip producing zone wherein said tools enter, engage said pieces of wood to produce chips and exit therefrom, said rear wall being at the exit end of said zone, at least a portion of said rear wall end including that part thereof which defines said zone being positioned to form an angle of substantially to 100 with the tangent to the circumferential path of travel of said cutting tools substantially at the terminal end of said portion, said portion being further positioned so that it is substantially perpendicular to a horizontal plane disposed substantially parallel to said axis of rotation of said carrier, that wall of said channel opposite said rear wall having a rigid moutning to prevent movement toward and away from said rear wall, each of said cutting tools having a mounting upon said carrier such that each tool is inclined in the direction of travel past said rear wall and is in a plane which intersects said portion of said rear wall at an acute angle when said tool is substantially opposite said portion, said portion of said rear wall being so located relative to the direction of rotation of said carrier and so disposed laterally of said axis of rotation of said carrier that when each tool of said carrier in rotational travel arrives substantially'at said potion it provides an upward motional component, said pieces of wood being moved toward and against said rear wall solely by rotation of said tools.

2. The apparatus of claim 1 wherein said portion of said rear wall is positioned to form an angle of substantially -95 with the tangent to the circumferential path of travel of said cutting tools substantially at the terminal end of said portion.

3. The apparatus of claim 1 characterized by said portion of said rear wall being a fixed blade and being disposed substantially transversely of said path of travel.

References Cited by the Examiner UNITED STATES PATENTS 2,634,062 4/1953 Forman.

2,969,095 1/1961 Brookhyser et al. 144162 X FOREIGN PATENTS 1,189,008 3/1959 France.

WILLIAM W. DYER, JR., Primary Examiner. 

1. APPARATUS FOR MAKING CHIPS FROM WOOD FOR CHIPBOARD COMPRISING A HORIZONTALLY POSITIONED, ROTATABLE DRUM-LIKE TOOL CARRIER WITH A HORIZONTAL AXIS OF ROTATION, A VERTICALLY DISPOSED CHANNEL FOR RECEIVING AND CONVEYING PIECES OF WOOD TO SAID TOOL CARRIER WHICH HAS A PLURALITY OF SPACED APART CHIP FORMING TOOLS EACH WITH A CUTTING EDGE AND WHICH IS ADAPTED TO BE DRIVINGLY CONNECTED TO MOTOR MEANS FOR IMPARTING ROTATION TO SAID CARRIER AND THEREBY TRAVEL TO SAID TOOLS, SAID CHANNEL BEING FORMED BY WALLS INCLUDING A REAR WALL, EXTENDING TOWARDS SAID CARRIER AND HAVING A TERMINAL END LOCATED SHORT OF ENGAGEMENT WITH SAID TOOLS TO FORM A CLEARANCE FOR TRAVEL OF SAID TOOLS THEREPAST, SAID WALLS AT SAID TERMINAL END DEFINING A CHIP PRODUCING ZONE WHEREIN SAID TOOLS ENTER, ENGAGE SAID PIECES OF WOOD TO PRODUCE CHIPS AND EXIT THEREFROM, SAID REAR WALL BEING AT THE EXIT END OF SAID ZONE, AT LEAST A PORTION OF SAID REAR WALL END INCLUDING THAT PART THEREOF WHICH DEFINES SAID ZONE BEING POSITIONED TO FORM AN ANGLE OF SUBSTANTIALLY 80* TO 100* WITH THE TANGENT TO THE CIRCUMFERENTIAL PATH OF TRAVEL OF SAID CUTTING TOOLS SUBSTANTIALLY AT THE TERMINAL END OF SAID PORTION, SAID PORTION BEING FURTHER POSITIONED SO THAT IT IS SUBSTANTIALLY PERPENDICULAR TO A HORIZONTAL PLANE DISPOSED SUBSTANTIALLY PARALLEL TO SAID AXIS OF ROTATION OF SAID CARRIER, THAT WALL OF SAID CHANNEL OPPOSITE SAID REAR WALL HAVING A RIGID MOUNTING TO PREVENT MOVEMENT TOWARD AND AWAY FROM SAID REAR WALL, EACH OF SAID CUTTING TOOLS HAVING A MOUNTING UPON SAID CARRIER SUCH THAT EACHTOOL IS INCLINED IN THE DIRECTION OF TRAVEL PAST SAID REAR WALL AND IS IN A PLANE WHICH INTERSECTS SAID PORTION OF SAID REAR WALL AT AN ACUTE ANGLE WHEN SAID TOOL IS SUBSTANTIALLY OPPOSITE SAID PORTION, SAID PORTION OF SAID REAR WALL BEING SO LOCATED RELATIVE TO THE DIRECTION OF ROTATION OF SAID CARRIER AND SO DISPOSED LATERALLY OF SAID AXIS OF ROTATION OF SAID CARRIER THAT WHEN EACH TOOL OF SAID CARRIER IN ROTATIONAL TRAVEL ARRIVES SUBSTANTIALLY AT SAID PORTION IT PROVIDES AN UPWARD MOTIONAL COMPONENT, SAID PIECES OF WOOD BEING MOVED TOWARDS AND AGAINST REAR WALL SOLELY BY ROTATION OF SAID TOOLS. 